Fertilizer-grain drill



April 22, 1958 B. J. SCHILL FERTILIZER-GRAIN DRILL 4 SheetS -Sheet 1 Filed May 28. 1953 INVENTOR. BERNARD J. SCHILL ATTORNEYS A ril 22, 1958 B. J. SCHILL FERTILIZER-GRAIN DRILL 4 Sheets-Sheet 2.

Filed May 28, 1953 INVENTOR. BERNARD J. SCHILL April 22, 1958 B. J. SCHILL 2,8

FERTILIZER-GRAIN DRILL Filed May 28, 1953 4 Sheets-Sheet 3 iNVENTOR. 73 BERNARD J. SCHILL BY Jam, Z Mam AT TOhNEYS GRAIN DRILL 4 Sheets-Sheet 4 Filed May 28, 1953 .IHII H #2 mm mm. NM

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INVENTOR. BERNARD J. SCHILL ATTORNEYS United States Patent FERTILIZER-GRAIN DRILL Bernard J. Schill, Rockford, 111., assignor to J. I. Case Company, Racine, Wis., a corporation of Wisconsin Application May 28, 1953, Serial No. 358,060

Claims. (Cl. 111-52) the amount of seed tendered into the furrows is directly proportional to the speed of such driver-support wheel. It is well known that when a vehicle progresses in a turning movement the outer wheel of the vehicle, rela tive to the turn, will advance more rapidly than the inner wheel.

drill is deviated from its normal straight-line seeding course, the speed of the support wheels will vary, and

accordingly, in drills of the more common-type, the amount of seed distributed at such point of deviation will also vary.

Since it is common practice, in certain parts of the country, to plant grain in the fall of the year while the fields may be obstructed at irregular intervals, as by standing corn shocks, a type of fertilizer-grain drill has been developed which will distribute a substantially uniform quantity of seed independent of the variable wheel speeds occasioned as the drill is maneuvered over an irregular planting pattern. However, the driving means utilized for the seed and fertilizer feeder mechanism of this latter type drill, prior to this invention, have invariably been of a rather complex design, and the drill structure and supporting frame accompanying such driving means was necessarily of like complexity in order to lend sufficient strength to resist the forces on the machine during fairly rough seeding operations.

It is the primary object of the present invention, therefore, to provide an improved fertilizer-grain drill which shall overcome the disadvantages and deficiencies of the prior structures. More particularly it is the object of this invention to provide a grain drill having an improved structural arrangement, including a novel drive means for the seeder mechanism affording a substantially uniform distribution of seed, which presents a particularly durable machine having its hopper disposed in relatively close relation to the ground and yet having the drive means for the seeder mechanisms associated with the hopper readily accessible for servicing and adjustment, A further object of the invention is to provide a machine of the type described which is of simplified and economic construction. vention will become apparent as reference is had to the accompanying disclosure.

In the drawings:

Fig. 1 is a fragmentary, side view of a grain drill provided with a novel drive clutch mechanism in accordance with the invention;

Fig. 2 is a fragmentary, top plan view of the triangular drawbar attached to the drill;

Fig. 3 is a fragmentary, bottom, perspective view,

It is apparent therefrom that whenever at Other objects and advantages of the intribntion of grain seed and fertilizer whenever the furand are not shown.

, 2,831,444 Patented Apr. 22, 1958 ice which illustrates certain features of the drive means for the seeder and fertilizer feeder mechanisms;

Fig. 4 is a detailed'illustration of the gear train which operates the-fertilizer feeder mechanism;

Fig. 5 illustrates an exploded, perspective view of the clutch mechanism associated with the left-hand support wheel;

Fig. 6 is a detailed, end view of the left-hand clutch drive with the cover plate broken awayto'more clearly illustrate the clutch details;vand

Fig. 7 is a side, elevational, view partly sectional, of the left-hand drive clutch, its supporting members, and the clutch and chain drive arrangement associated with the seed-feeder mechanism.

The illustrated structure includes a frame 11 mounting a sheet metal seed and fertilizer hopper 14 having individual compartments 13 and 16 for separately retaining the seed and fertilizer therein while the planting operation is being performed. A triangular drawbar 17 extends forward from the frame to form attachment means for connecting the drill to an associated draft vehicle. Frame 11 and its associated structure are supported by a pair of standard, small sized, pneumatic tire wheels 19, which in their rotational movement over the ground, effect simultaneous rotation of the sprockets 21 attached to their individual hubs '73. A chain 23 cooperates with each of the sprockets 21 to operatively connect an overrunning drive clutch Z5 to the associated support wheel for selectively controlling operation of a jack shaft 27. Each of the drive clutches 25 is a novel construction and constitutes an important feature of the invention, as will hereinafter appear.

Seed and fertilizer feeding mechanisms which'determine the amount of grain and fertilizer to be distributed and the time of suchdistribution, are driven by means of inter-related gear trains and clutch mechanisms connected to the jack shaft 27. The drive clutches 25 are keyed to the respective ends of the jack shaft 27, the shaft being normally operated responsive to rotation of the drive-clutch pair as the support wheels progress along a comparatively straight-line seeding path. However, whenever the drill is deviated from such course in a turning movement, one wheel will obviously rotate more rapidly than the other, whereupon the overrunning drive clutch associated with the slower moving wheel is arranged to disengage its driving member and allow the faster moving wheel to independently drive the jack shaft and its associated mechanism.

The seed and fertilizer feeder arrangements are of conventional type and are intended to be connected to a plurality of chutes, not shown, each chute extending from the hopper bottom portion to a point adjacent the disc type furrow openers 29, which are pivotally supported on dragbars 31 extending downwardly from the frame. Selective metering means (not shown) which are associated with the feed gates of the seeder and fertilizer arrangements, and selective speed arrangements associated therewith operate to determine the quantity of grain and fertilizer to be distributed. Controls extending forward from the drill to a point adjacent the operator are operative to raise and lower the furrow openers to any desired depth, and a lift bar arrangement, likewise controlled by the operator, is operative to bias the furrow openers into and out of engagement with the soil, as desired. These arrangements are Well known in the art Control links 32 and 34 extend from the lift bar mechanism to a pair of clutches 33 and 35 (Figs. 4 and 7); operation of the lift bar mechanism simultaneously actuating the clutches 33 and 35 through the action of the links 32 and 34 to terminate the disa row openers are disengaged from ground contact, and to initiate the seeding and fertilizer distribution whenever the furrow openers are biased into the ground. The fertilizer mechanism is also equipped with a hand duow lever 37 (Fig. 4), which, when operated to a predetermined position, disengages the fertilizer feed mechanism to thereby effect an independent seeding operation. Suitable covering mechanism, not shown, such as chains or rollers, are provided to cover the seeds as deposited in the furrows.

Referring to Figs. 1 and 3, the illustrated grain drill structure comprises a rectangularly shaped base frame 11, including a plurality of transverse frame members 39, comprising elongated angle sections which are interconnected by a plurality of short, longitudinally extend.- ing, stiffening members 41. A pair of horizontal angle members 43 and 45 (Fig. 2) are fastened to the front portion of the frame 11, and an upwardly and rearwardly inclined stiffening element 47 is attached to the forward surface of the metal feed hopper 13 by suitable fastening means. The forward ends of the structural elements 43, 45 and 47 are rigidly bolted to a face plate disposed at their forward ends thus to define the triangularly shaped drawbar 17, and a hitch post 4-9 is attached to the forward end of the drawbar so formed,

The combination grain-fertilizer structure 11 is con nected to the frame, fore and aft, by suitable brackets 51 and 53. On the feed hopper face, a set of braces 51 conform to a portion of the face contour and extend downward to the frame 11, bolt means connecting the braces 51 to the frame and hopper. ,The rearward face of the hopper is strengthened by a set of braces, such as the braces illustrated at 53,which conform to the hop.-

per contour and which are connected both to the frame 11 and to the inner end of the Wheel support axles b as by the bolts 54 shown in Fig. 3.

It will be noted that the braces 51 and 53 are bolted to the frame and to the sheet metal hopper 14, which is desirably constructed of fairly heavy gauge material. The hopper 14 includes metal divisions and an upwardly curved bottom, and thus possesses the characteristics of a hollow beam of considerable rigidity, which in cooperation with the rectangular frame aids in providing an extremely strong and durable implement. Additionally, the lower end of each of the two outer hoppenbraces 53 is bolted both to the frame 11 and to the inner end of one of the wheel supporting axlesSt). This arrangement materially strengthens the structure and aids in preventing misalignment of the control shaft and the interrelated gear mechanism.

As previously described, each end of the drill frame 11 is supported on a standard, small size, pneumatic tire wheel 19, which is journaled on a depending crank axle construction 55, the axle being angled so as to provide a desirable clearance between the frame 11 and the ground level for installation of grain chutesand furrow openers 29. As more clearly illustrated in Figs. 1, 3, and 5 the axle construction comprises a bent shaft having spaced-apart, generally parallel arm and spindle sections 50 and 52, respectively, joined by an integral right-angled connecting portion 56 which depends from the arm 50 downwardly to the spindle 52 in a plane transversely of the arm and spindle sections. The arm 50 is adapted to be connected to the rear transverse frame member 39 and the brace 53 by a single bolt 54, or other suitable fastening means, and the spindle 52 provides a journal for mounting the support wheel 19, such journal supporting section being disposed below the rear frame 39 substantially as illustrated in Fig. 3

The connecting portion 56 (as shown in Fig. 1.) is attached to the side member 15 of the frame by means of a hook clamp 61, whose arcuate section encompasses the connecting section of the axle and whose threaded shank is bolted into the stiffening member 15. The connecting portion 56 of the axle is angled downwardly Fing portion 56 (Fig. 5).

casting is attached to the axle at the junction of the wheel supporting spindle 52 and the depending connect- I Connecting flanges on the bracket allow attachment thereto of the bracing member 69, which extends upward to the outer stiffening member 15. v i

The inner portion of the bracket 63 is shaped to the I contour of the bend forming the wheel supporting or journal section 52 and the depending connecting portion 56 of the axle, and the connecting flanges of the bracket are drilled with suitable holes for receiving the shanks of a U-bolt 65, which encompasses the connecting portion 56 of the shaft and attaches the bracket thereto. The bracing member 69 is a generally, vertically extending, fiat steel strap, which is drilled for connection to the clamp: ing portion of the bracket 63 and the axle by the threaded legs of the U-bolt 65, as illustrated. The upper end of the bracing member is provided with a knee or otfset sec-. tion, which is adapted to engagethe lower surface of the stiffening member 15. The upper end of the bracing member 69 is attached to the frame member 15 so that the weight of the implement is borne by the offset sec,- tion of the bracing member.

The support wheel 19 includes a hub or bearing section 73 of'greater diameter than the journal section to allow my copending application Serial No. 49,603, filed Septem-I ber 16, 1948, now Patent No. 2,678,708, patented May 18, 1954.

Each support wheel hub 73 carries a sprocket 21 (Figs;

1 and 5), operatively connected to one of the drive clutch mechanisms 25 by means of a suitable chain 23. Each drive clutch 25 is rigidly supported by an individualsup: port bearing 75 the drive clutch being composed basically of a main gear 79 and a gear face plate 91, each of said drive clutches 25 being effective at times to transmit dl'lV-r ing power from the drill support Wheels to a jack shaft 27 for operating the drill seed and fertilizer arrangements connected thereto. In more detail, as seen particularly in Fig. 6, the hollow main gear 79 locates an outer flange rim having a set of gear teeth 77 which are integral with its outer periphery and an integral inner gear tooth segment 81 on the inner periphery thereof. The teeth of the inner segment 81 are shaped for operative engagement with the angled surfaces of pawl members 83 which are supported on the face plate 91. The gear face 85, located on the frame side of the main gear 79, is formed integral with the outer flange rim which mounts the dual gear tooth segments, and as more clearly illustrated in.

Fig. 7, includes an integral center-bored, bearing stem or boss 87. The outer circumference of the bearing stem 87 is designed for bearing engagement with the inner circumference of the bearing support member 75. The main gear wheel 79 rotates with the bearing stem 37 about their common axes as rotational movement is imparted to the gear wheel 79 by the associated chain 23, hub sprocket 21 and support wheel 19. The outer face plate 91 is fashioned to rest within the recess formed by the inner gear tooth segment 81 and the outer rim of the main gear 79, and this plate carries a center-bored cylindrical stem 93, which fits within the bore of the main gear stem or boss 87 with a bearing fit. Thus when the face plate stem 93 is inserted within the main gear stem 87, both the face plate 91 and the main gear 79 may be rotated with and about their individual stems, independent of each other and the support bearing 75 which mounts them.

Each pawl member 83 has a sharp-angled face 84 and a shallow-angled face 86 at its outer end, both faces approximating the shape of the indentations formed between the gear teeth 81. The pawls are pivotally mounted about studs 95 fastened on the face plate 91, and are normally encouraged to a position directionally outward of the face plate center by associated springs 97. Therefore, the pawl members, because of their shape and their location relative to the inner gear teeth 81, are normally forced into operative engagement with the indentations between such teeth by the springs 97, substantially as shown in Fig. 6. Arcuate finger projections 99, which are cast integral with the face plate 91, encompass the lower extremities of each pawl to form a limited bearing surface for accepting forward thrust components of the pawl member and transmitting such motion to the face plate and associated jack shaft 27, the face plate 91 being keyed thereto by a key 101 located in a recessed keyway 103 (Fig. 5). The outer face of the arcuate fingers 99 form a bearing surface with the gear teeth 81, which is desirable Whenever the jack shaft 27 and the face plate 91 rotate at a greater velocity than the main gear 79 as hereinafter described.

In operation, as the inner gear teeth 81 move in a counterclockwise direction, as shown by the arrow 82 in Fig. 6, upon actuation of the main gear 79 by the chain drive 23 and the associated support wheel 19, the pawls 83 are maintained in engagement with the inner gear teeth 81 by the spring elements 97 to thus carry the pawls 83 along in their counterclockwise, rotational movement. Pawls 83 transmit the pressure thrust to the arcuate fingers 99 to cause like movement of the face plate 91 and the jack shaft 27 keyed thereto. The clutch 25 on the opposite end of the shaft functions in a similar manner, and as the drill progresses over a fairly regular path, the clutches will act concurrently to motivate the jack shaft. However, whenever the drill is deviated from its normal path, as for example in a turning moment, the inner wheel, relative to the turn, will travel at a slower speed than the outer wheel of such turn. The outer Wheel, which has a greater velocity, thus imparts its movement to its associated drive clutch 25, the pawls 83 of which will remain in engagement with the integral inner gear teeth 81 to drive the jack shaft 27 at a similar speed of rotation in a manner heretofore described. The face plate 91 associated with the clutch 25 of the inner Wheel of the turn, because of its keyed connection to the jack shaft 27, will rotate at jack shaft speed, and the pawl members 83, because of its shallow angle face 86, will slip over the tooth segment 81 of the slower moving main gear. The face plate 91 and main gear 79 of the drive clutch associated with the slower moving wheel are thus independently rotated about their individual bearing stems at different speeds.

It will be noted that the outer rim of the main gear 79 extends beyond the inner tooth segment 81 to form a recess for receiving face plate 91, the flange and plate cooperatively affording protection against entry of foreign substances within the drive clutch bearings.

The seed feeder mechanism in the particular apparatus illustrated in Fig. l is driven from a square shaft 117 and a combination sprocket and gear 119 supported at the end of the hopper 14. The gear section of the combination gear and sprocket 119 mesh with a gear 121 on the seeder drive shaft 117, and the sprocket section is operatively connected to the jack shaft 27 by chain 125 and a spring clutch 115 (Fig. 7). Suitable idlers and chain tighteners 123 (Fig. l) are provided for chain 125. Whenever spring clutch 115 (Fig. 7) is actively engaged with the cam piece 111, movement of the jack shaft 27 will operate the seeder shaft and the feeder mechanism which is attached to the seeder shaft at regular intervals.

The forward face of the spring clutch 115 locates notched teeth 127 which engage similar teeth formations on the rearward face of the cam member 111, normal engagement of these teeth being effected by a coil spring 129 which is disposed about the jack shaft 27, between key 131 and the rear face of the spring clutch 115. Consequently, when the clutch 115 is in the driving position, movement of the jack shaft imparts rotation to the clutch and the sprocket sets 133 and 135 located on the clutch outer periphery to drive the associated chain 125 and the seed feeder shaft 117.

A control link 32 (Fig. 7) extends between the lift bar arrangement (not shown) and the clutch arm 13']. Whenever the furrow openers 29 are raised by operation of the lift bar, the control link 32 moves the clutch arm 137 into contact with an angled projection 139 located on the support bearing 75, whereby the arm 137 and its associated cylindrical body are moved laterally against the spring clutch 115 to overcome pressure of spring 129. Clutch 115 is thereby disengaged from the rotating cam element 111, and rotation of the clutch and its associated sprockets 133 and 135 is terminated. Operation of the furrow lift bar mechanism to bias the furrow openers 29 into the ground allows the arm 137 to return to the illustrated position, and the spring clutch 115 engages cam 111 responsive to the pressure of spring 129. The pair of sprockets 133 and 135 mounted on the clutch are used interchangeably with chain 125, the selected sprocket being determinative of the speed at which the seed metering shaft is to operate.

In assembly, the support bearings, such as 105 (Fig. 3), are spaced at regular intervals along the shaft, and the spring clutch 115, the gear wheels 79, face plates 91 and the support bearings 75 are placed on their respective jack shaft ends. Key 101 (Fig. 5) is inserted into the jack shaft bore 102 and the face plate 91 is positioned so that the key 101 is received by recess 103, whereby the outer face of the face plate 91 will be located in a plane parallel with the jack shaft end. Main gear 79 is moved into engagement with the faceplate 91, the stem of the face plate 91 being cooperatively inserted Within the bore of the main gear stem 87, and support bearing -75 is then positioned to receive and support the, outer circumference of the main gear stem 87. Cam piece 111 (Fig. 7), the inward face of which bears a tooth segment for cooperating with a like surface located on spring clutch 115, is thereupon keyed to the jack shaft by key 113 to retain the drive clutch elements in their assembled positions. It isobvious that the keys 101 and 113 will prevent lateral movement of the drive clutch on the shaft. The support bearings 75 are then attached to the frame member 15,

after which the spring clutch may be moved into active engagement with cam 111 and keyed to the jack shaft 27 by key 131.

Jack shaft 27 also cooperates with a chain linkage 141 which extends to the main sprocket wheel 143 of the fertilizer-grain drill mechanism, as shown in Figs. 3 and 4, to provide simultaneous operation of'the fertilizer drive shaft 145 therewith. A link member 34 connected to the furrow lift bar mechanism is operated in a manner similar to that of the seed feeder link member 32; that is, as the furrow openers 29 are engaged with the ground, the link member 34 operates clutch 35- to effect connection of the gear mechanism 149 to the shaft 145. Whenever the furrow openers 29 are disengaged from ground contact, the lift arm returns to its normal position to disengage the fertilizer-grain mechanism 149 from the shaft 145. A

hand-throw out clutch allows the operator to disengage the fertilizer-grain mechanism 149 from the shaft 145,

as desired, operation of the link mechanism and furrow opener lift bar thereafter being ineffective to operate the fertilizer feeder shaft 151. Conventional type feeder elements, such as 153, are attached at regularly spaced intervals along the shaft 151 and operated responsive to operation of the shaft.

'It is obvious that the novel clutch drive of the invention, because of its simple design, may be readily adapted to other types of machine implements. The simple and sturdy structure of the disclosed arrangement facilitates rapid assembly of the clutch and the implement used therewith. Further, the desirable design of the drive clutch, as set forth, insures free access to the various inter-related working mechanisms of the associated implement for adjustment and repair purposes.

Consequently, it is seen that apparatus constructed in accordance with the disclosed invention provides an improved form of drive mechanism for the feed mechanisms, which is combined in a novel manner with an improved frame and wheel support arrangement to present a more durable grain drill construction. Furthermore, the particular arrangement of elements described herein provides ready access to the various working mechanisms while maintaining a desirably low position for the hopper and feed mechanisms.

1 claim:

1. In a grain drill, the combination of a generally rectangular, elongated frame structure including a pair of transverse members spaced fore and aft with respect to the normal direction of travel of the grain drill and joined at their ends by a pair of side frame members, an elongated seed hopper supported on said frame, seed feeding mechanism associated with said hopper, a drawbar structure secured to the forward part of said frame structure and extending forwardly therefrom, brace means extending from a forward portion of said drawbar structure to an upper portion of said hopper, a jack shaft rotatably mounted on the underside of said frame in bearing supports fixed to each of said side frame members. an overrunning clutch mechanism concentrically mounted with said jack shaft in each of said bearing supports for operative connection with the associated end of said jack shaft, a crank axle fixedly mounted on each of the opposite ends of one of said transverse frame members in depending relation thereto, a support wheel rotatably mounted on each of said crank axles, and power transmitting means connecting each of said rotatable support wheels with the associated overrunning clutch mechanism, whereby said seed feeding mechanism will be operated at a rate of speed determined by the fastest moving one of said support wheels.

2. In a grain drill, the combination of a generally rectangular frame structure including a pair of elongated transverse frame members spaced fore and aft with rcspect to the normal direction of travel of the grain drill and joined at their ends by a pair of side frame members, an elongated hopper structure fixedly supported on said frame between said side frame members, material distributing mechanism associated with said hopper structure, a drawbar structure secured to the forward part of said frame structure and extending forwardly therefrom, brace means extending from a forward portion of said-drawbar structure to an upper portion of said hopper, a jacl; shaft rotatably mounted on the underside of said frame in aligned bearing supports fixed to each of said side frame members, a pair of crank axles fixedly mounted on opposite ends of the rearward one of said transverse frame members in depending relation thereto and presenting lower spindle portions projecting laterally outwardly from said frame structure, a support wheel rotatably mounted on the spindle portion of each of said crank axles, power transmittiru means connecting each of said rotatable support wheels with said jack shaft and connecting the latter with said material distributing mechanism, additional brace means extending from an upper portion of the rearward side of said hopper to the rearward transverse frame member at a position adjacent each of said crank axles, and means rigidly interconnecting said additional brace means, rearward frame member and said crank axle.

3. in a grain drill, the combination of a generally rectangular frame structure including a pair of elongated transverse frame members spaced fore and aft with respect to the normal direction of travel of the grain drill and joined at their ends by a pair of side frame members, an elongated hopper structure fixedly supported on said frame between said side frame members, material distributing mechanism associated with the lower portion of said hopper, a drawbar structure secured to the forward part of said frame structure and extending forwardly therefrom, brace means extending from a forward portion of said drawbar structure to an upper portion of said hopper, a jack shaft rotatably mounted on the underside of said frame in aligned bearing supports fixed to each of said side frame members, an overrunning clutch mechanism concentrically mounted with said jack shaft in each of said bearing supports for operative connection with the associated end of said jack shaft, a pair of crank axles fixedly mounted on opposite ends of the rearward one of said transverse frame members, each crank axle including a generally horizontal upper section, a depending section, and a lower spindle portion for rotatably mounting a support wheel, additional brace means extending from an upper portion of the rearward side of said hopper to the rearward transverse frame member adjacent said upper section of said crank axle, means rigidly interconnecting said additional brace means, upper axle section and said rearward transverse frame member, and power transmitting means connecting each of said rotatable support wheels with the associated overrunning clutch mechanism and connecting said jack shaft with said material distributing mechanism.

4. In a grain drill, the combination of a generally rectangular frame structure including a pair of elongated transverse members spaced fore and aft with respect to the normal direction of travel of the grain drill and joined at their ends by a pair of side frame members, an elongated hopper structure fixedly supported on said frame between said side frame members, material distributing mechanism associated with the lower portion of said hopper structure, a drawbar structure secured to the forward part of said frame structure and extending forwardly therefrom, brace means extending from a forward portion of said drawbar structure to an upper portion of said hopper structure, a jack shaft rotatably mounted on the underside of-said frame in bearing supports fixed to each of said side frame members, a pair of crank axles fixedly mounted on opposite ends of the rearward one of said transverse frame members, each crank axle including an upper horizontal section, a depending section, and a lower spindle portion for rotatably mounting a support wheel, and power transmitting means connecting each of said rotatable support wheels with said jack shaft and connecting the latter with said material distributing mechanism.

5. In a grain drill, the combination of a generally rectangular frame structure including a pair of elongated transverse members spaced fore and aft with respect to the normal direction of travel of the grain drill and joined at their ends by a pair of side frame members, an elongated hopper structure supported on said frame between said side frame members, material distributing mecha' nism associated with said hopper structure, a jack shaft rotatably mounted on the underside of said frame in bearing supports fixed to said side frame members, means drivingly connecting said jack shaft with said material distributing mechanism, a pair of crank axles fixedly mounted on each of the opposite ends of the rearward one of said transverse frame members, a support wheel rotatably mounted on each of said crank axles, additional power transmitting means connecting each of said rotatable wheels with the associated end of said jack shaft, brace means extending from an upper portion of the rearward side of said hopper structure to the rearward transverse frame member adjacent each of said crank axles, and means rigidly interconnecting said brace means, said rearward frame member and said crank axle.

References Cited in the file of this patent UNITED STATES PATENTS 222,316 Shephard Dec. 2, 1879 10 Franklin May 31, 1887 Van Brunt Jan. 31, 1893 Armitage Jan. 1, 1901 Hyland Ian. 1, 1946 Hyland Feb. 21, 1950 Schill June 9, 1953 FOREIGN PATENTS Australia Apr. 10, 1941 

